<!--
 * @Description: 块元素
 * @Author: charles
 * @Date: 2021-08-09 10:53:11
 * @LastEditors: charles
 * @LastEditTime: 2021-08-09 11:26:35
-->
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>块元素</title>
  <style>
    /* 重置样式 */
    body {
      margin: 0;
    }
    p {
      margin: 0;
    }
    ul,dl,ol {
      margin: 0;
      padding: 0;
      list-style: none;
    }
    dl > dd {
      margin: 0;
    }
    ul.menu > li {
      line-height: 2em;
      background-color: #ccc;
      border-bottom: 1px solid #fff;
    }
  </style>
</head>
<body>
  <div>this is first div</div>
  <div>this is second div</div>
  <div>this is third div</div>
  <p>段落1</p>
  <p>段落2</p>

  <ul class="menu">
    <li>html</li>
    <li>css</li>
    <li>js</li>
  </ul>

  <ol>
    <li>vue</li>
    <li>react</li>
    <li>angular</li>
  </ol>

  <dl>
    <dt>学生管理</dt>
    <dd>学生档案</dd>
    <dd>学生请假</dd>
    <dd>学生就业</dd>
    <dd>学生考试</dd>
    <dt>教师管理</dt>
    <dd>教师考勤</dd>
    <dd>教师薪资</dd>
  </dl>

  <h1>标题1</h1>
  <h2>标题2</h2>
  <h3>标题3</h3>
</body>
</html>